Predicting the outcome of the greater occipital nerve block – an observational study on migraine patients with and without musculoskeletal cervical impairment

Abstract

Background and objective The importance of neck pain and the trigeminocervical complex in migraine is of high pathophysiological interest since a block to the greater occipital nerve is more effective for some primary headaches than others. This observational study hypothesised that the response to manual palpation of the upper cervical spine predicts the efficacy of the greater occipital nerve-block. Methods We divided patients, scheduled by a neurologist to receive a greater occipital nerve-block to reduce their migraine symptoms, into three groups: Patients with no pain response to manual palpation of the neck, patients with local pain, and those with referred pain to the head. Primary outcome was the percentage change in headache frequency. Additionally, items from the quantitative sensory testing protocol were included. Results Eighty-seven chronic migraine patients were recruited consecutively from a specialised outpatient clinic and 71 were included for analyses and stratified into the three groups: No pain (n = 11), local pain (n = 28), and referred pain to the head (n = 32). Overall, patients experienced a reduction of 1.9 headache days per month (SD 3.4, p < 0,0001). The groups differed significantly in the percentage change of headache frequency ( p = 0.041) with the “no pain” group showing the largest reduction. The pressure-pain-threshold over C2 and headache on the day of the intervention influenced the outcome significantly (R2 0,27, p = 0,00078). No serious adverse events occurred. Sixty-five percent of the patients had headaches during the examination. The groups did not differ regarding the distribution of patients with neck-pain in absence of migraine at baseline ( p = 0.618). Conclusion Patients that were less sensitive to palpation in the cervical region and headache-free on the day of the intervention improved more after the greater occipital nerve-block. Registration: Registered a priori at the German Clinical Trials Register (DRKS00015995).

Experimental evidence of a functional relationship within the brainstem trigeminocervical complex in humans

“…Interestingly, a disruption of such essential functionalities may contribute substantially to the radiation of some types of chronic pain, 27 which may explain why in migraine and some other primary headaches many patients also have neck pain. 20,29…”

“…12,25 It needs to be pointed out that a sensitisation of the occipital system does not predict whether a GON block is effective in treating the headache because patients who are less sensitive in the cervical region has shown to improve more after a GON block. 29 Overall, objective evidence for this pathophysiological mechanism of reciprocal relationships in humans is scarce, and the question whether such a functional interconnection is unidirectional from the neck to the head or also vice versa is not known. We focussed on this topic and investigated this relation using electrical pain thresholds (EPTs) in the interplay between the trigeminal and the occipital system in healthy participants following the standardised topical application of capsaicin as a sensitising agent.…”

Only Cervical Segments C0-C2, Not C3 Are Relevant for Subgrouping Migraine Patients According to Manual Palpation and Pain Provocation

“…Therefore, it must be investigated whether the test results of C3, C2 and C1 can be summarized for the strati cation of migraine patients. The aim of this secondary analysis of a cohort study [11] was therefore to analyze whether palpation points at C1-3 form one underlying construct using item-response-theory (IRT).…”

Pain sensitivities predict prophylactic treatment outcomes of flunarizine in chronic migraine patients: A prospective study

“…Identification of predictors of treatment outcomes is of clinical significance and importance. Factors reported to be associated with poor treatment outcomes include comorbid depression (3), medication overuse (3), longer disease durations of CM (4) or migraine (5), chronic headache (6–8), and signs of central sensitisation (i.e., increased pain sensitivity or allodynia) (9–13). However, most of these studies determined the presence or severity of pain hypersensitivity by questionnaires (6–8,11) rather than objective measurements.…”